This is an application from the Division of Nephrology at the Duke University Medical Center to participate as a clinical center in a NIH sponsored cooperative study aimed at reducing morbidity and mortality in patients with end-stage renal disease. This proposal focuses exclusively on patients receiving incenter hemodialysis and conforms to the criteria set forth in the NIH Guide entitled "Morbidity and Mortality in Hemodialysis Patients". This trial is a prospective, multicenter, randomized, 2 X 2 factorial designed clinical trial. This trial is designed to compare two different classes of hemodialysis membranes and two levels of delivered dialysis (defined by the formula Kt/V, where K is the dialyzer urea clearance in ml/min, t is the treatment time in minutes, and V is the body urea volume in milliliters) on patient morbidity and mortality. The Kt/V delivered dialysis target in 50% of the patients will be 0.9-1.1. The Kt/V delivered dialysis target in the 50% of the patients will be 1.3-1.5. Within each of these delivered dialysis groups 50% of the patients will be dialyzed with a high-flux, biocompatible, dialysis membrane and 50% will be dialyzed with a low-flux, bioincompatible cellulosic membrane. The objectives of the study are to reduce mortality and morbidity in hemodialysis patients. The interventions will be the amount of delivered dialysis and the dialysis membrane employed. Mortality due to all causes will be the primary outcome. Secondary outcomes include rate of nonvascular access- related hospital admission, cardiovascular events, congestive heart failure, occurrence of infections, and decline in serum albumin. The role of the amount of delivered dialysis and the type dialysis membrane should be apparent by the end of the trial. The Duke University dialysis system proposes to enroll 60 patients into this multicenter protocol and comply with all aspects of the manual of operations.